1. Field of the Invention
This invention relates generally to an exercise device. More particularly, the invention concerns an exercise device permitting a user to perform alternatively a stair stepping exercise or a cross country skiing exercise, or simultaneously to perform a stair stepping exercise and a cross country skiing exercise.
2. Description of Prior Art
Heretofore, various exercise devices have been provided to permit a user to perform a stair stepping exercise which simulates the climbing of stairs. Also, various exercise devices have been provided to permit a user to perform a cross country skiing exercise which simulates cross country skiing. However, none of the exercise devices heretofore have permitted in a single exercise machine, the simultaneous performance of a stair stepping exercise and a cross country skiing exercise. No prior exercise device has allowed a user to change the exercise he is doing while on the machine from stair climbing to cross country skiing to a bicycle-like motion to a backward walk motion, all without mechanical adjustment of the machine.
For example, U.S. Pat. No. 3,970,302 dated Jul. 20, 1976, shows an exercise device in which a pair of foot supports are mounted for movement along an inclined track to simulate stair climbing. A pair of shock absorbers connected to the foot supports resist downward movement resulting from a downward force exerted by the feet of a user and provide upward return movement of the foot supports to a predetermined position. There is no showing of an exercise movement simulating cross country skiing.
U.S. Pat. No. 4,685,666 dated Aug. 11, 1987, likewise shows an exercise device to simulate a climbing or stair stepping motion, but such exercise device does not provide a cross country skiing exercise.
U.S. Pat. No. 4,733,858 dated Mar. 29, 1988, shows a multi-purpose exercise device which may be utilized to perform various exercises. The device is used in a first position to practice climbing such as climbing steps. The device is adjusted to a second position to simulate a skating motion. There is no provision for performing a climbing exercise and a skating exercise simultaneously with the device remaining in one position.
U.S. Pat. No. 5,000,442 dated Mar. 19, 1990, shows a cross country ski simulator in which foot supports are mounted for generally horizontal back and forth movement with manually gripped handles controlling the movement of the foot supports and providing a resistance to the movement of the foot supports. Such ski simulator does not provide a simulated climbing or stair stepping exercise performed simultaneously with the cross country skiing exercise.